Re: One-To-One Relationships

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Fri, 30 Nov 2007 11:11:32 -0400
Message-ID: <47502827$0$5277$9a566e8b_at_news.aliant.net>

David Cressey wrote:

> "Bob Badour" <bbadour_at_pei.sympatico.ca> wrote in message
> news:474f8ba3$0$5284$9a566e8b_at_news.aliant.net...
> 

>>JOG wrote:
>>
>>
>>>On Nov 30, 12:53 am, David BL <davi..._at_iinet.net.au> wrote:
>>>
>>>
>>>>On Nov 30, 7:34 am, JOG <j..._at_cs.nott.ac.uk> wrote:
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>>On Nov 28, 10:37 pm, paul c <toledobythe..._at_ooyah.ac> wrote:
>>>>
>>>>>>Bob Badour wrote:
>>>>>>
>>>>>>
>>>>>>>rpost wrote:
>>>>>>
>>>>>>...
>>>>>>
>>>>>>
>>>>>>>>This is the exact problem Chen identified. In the relational model
>>>>>>>>it is impossible to have entity-valued attributes, which, in

> 
> practice,
> 


>>>>>>>>we have a huge amount of.


>>>>

>>>>>>>Entities are figments of our imaginations.

>>>>>>>...

>>>>
>>>>>>That's much better than my reply, looks like the essential point to

> 
> me.
> 


>>>>>Entities are concepts that we impose on that which is there (mostly


>>>>>shapes made out of atoms, but sometimes abstractions too).

>>>>

>>>>>Entities are 'real' in that they are patterns that we think up and

>>>>>apply, and 'not real' in that if we were all dead, well there wouldn't

>>>>>be any 'entities' would there. Just atoms again.

>>>>

>>>>Is this merely an argument against mathematical realism or something

>>>>more specific?

>>>

>>>

>>>I haven't argued anything, I have just defined entities. All seems

>>>like common sense to me.

>>>

>>>

>>>

>>>>>Because we conjure them up 'entities' aren't neatly defined, can

>>>>>overlap, change, and will differ from person to person. In fact its a

>>>>>testament to the amazing flexibilty of our noggins that  that we

>>>>>manage to communicate at all.

>>>>

>>>>Do you consider all mathematics to be "conjured up" and therefore not

>>>>neatly defined as well?

>>>

>>>

>>>Non-sequitur. I have made no comments on mathematics nor on anything

>>>being ill-defined.

>>>

>>>What I am suggesting is that given the contextual nature of how we

>>>define any given entity, any model centered upon them is going to have

>>>a very inflexible, brittle view of the world.

>>>

>>>There are a load of atoms. Someone else looks at them and says hey its

>>>a dead bit of wood, its a 'stump' entity. Someone else considers a

>>>bigger picture and says its a snapshot of a 'tree' entity. Me, being

>>>lazy, say hey I could sit on that, its a 'seat' entity, etc., ad

>>>infinitum.

>>>

>>>Whos right? Noone. Everyone. Who cares. It just depends on the

>>>context, and with shared data, thats gonna vary. So lets encode the

>>>underlying bloody information, and not whatever brittle view of the

>>>world that first pops into our heads, ending up with a brittle,

>>>creaking database.

>>>

>>>

>>>

>>>>>And as such, anyone who tells you that you can build a permanent, all

>>>>>encompassing model out of such utterly woolly things is not to be

>>>>>trusted as far as you can throw them.

>>>>

>>>>>P.S I have also had similar experinces at Ikea :) I don't follow the

>>>>>arrows anymore. They lie.

>>>>

>>>>If there is a valid argument against "entities" I would hope it can be

>>>>stated more carefully than your or Bob's attempts.

>>>

>>>

>>>Again I haven't argued against entities. However, I am of course
>>>interested in what you deem invalid in my comments.
>>
>>He didn't like the figment argument? I thought it was careful and quite
>>clear. Perhaps, I should elaborate:
>>
>>Entities are subjective and products more of applied psychology than
>>applied mathematics.
>
> So the subject matter is subjective. Why is that a criticism?

I disagree. Received on Fri Nov 30 2007 - 16:11:32 CET